Spiraled seat releasing and circulating overshot



NOV. 4, 1952 3, w QSMUN 2,616,752

SPIRALED SEAT RELEASING AND CIRCULATING OVERSHOT Filed Feb. 26, 1946 Patented Nov. 4, 1952 UNITED STATES PATENT OFFICE.

SPIRALED SEAT RELE smc'ANn- CIRCULATING OVERSHOT Dean W. Os'mun, Houstom T'ex.

Application fieliruarylzfi, 1946, Serial No. 650,264 9"Claini's.' (Cl. 294 102)" 1; This invention" relates to a' spiralled" seat releasing and circulating overshot.

This invention constitutes certain improvementsover that type of releasing and circulating overshot disclosed in my co-pending application filed December 26,1946, under Serial No. 650,265

which became Patent No. 2,491,392 on December An object of the invention is to providea tool of the character described speciallydesi'gned for removing stuck objects, such as pipe and the like from wells, and which is so designed that a given size of overshot mayengage stuck pipe; or other stuck objects of variable transverse diameters.

It is another object of the invention to provide atool of the character described which is'of very simple construction andwh'erein the engaging grapple will engage or release the stuck object up'on appropriate manipulation of the tool without additional auxiliary engaging or releasing mechanism.

It'is a further object of the invention to provide an overshot' of the character described which may be telescoped to any desired distance over the object to be engaged and pulled out:

'With the above'and other'objects in view the invention has particular relation to certain novel features of construction, arrangement of parts and use,- anexample of which is given in this specification and illustrated in the accompanying drawings, wherein:

Figure 1 is a vertical sectional view of the tool.

Figure 21s a cross sectional view takenon-the line 2'2 of Figure 1.

Figure 3-is a vertical sectional view taken on the line 3-3"of Figure 1.

Figure 4 is a side view of the grapple,-and- Figure 5 is a bottomend viewof the grapple illustrated in Figure 4.

Referringnow more particularly to the drawingswhereinlike numerals of reference desige nate the same parts in each of the-figures, the numeral 1 designates the bowl which is of ageneral tubular. form and whose-upper .endmay be internallythreaded for the connection of anoperating string. 2 thereto.

The lower end of the bowlmay be reduced and externally threaded to receive theupper end oftheguide ii, which is screwed onto the bowl. Thisguide is tubularin formand beneath the bowl it isinwardly thickened and its lower endisflared, internally, so as to more readilytelescope over the stuckobject to bepulled.

The lower end of the bowl is internally counter s forming an annular recess or grooved:

2 Above the recess l-the bowl-is formed'with'an' inside, spiralled, downwardly convergingseat -a'i and above said seat is provided with aportion forming a downwardly facing shoulder having an undercut spiralled groove or recess 6.

There is a grapple 1 whose lower end is formed into a tension ring 8 having the notch 9 in one side thereof so that it will be expansible, and

formed integrally with the ring and upstanding therefrom the grapple is formed withthe jaws to, which are'separated by longitudinal slits H;

These slits extend from the ten's'ionring to the upper end of the grapple, as shown in Figures.

The grapple is formed with the external, spiralled, downwardly tapering'fa'ce, or seat; i2, which is shaped to'con-form to, and which rides against, the seat 5-, and the seator iacelr terminates in an upwardly facingshoulderformed with the upwardly directed spiralled edge I3.

This edge is spaced beneath the groove 6:

The-jaws i0 have the inside-spiralled teeth 14 forming threads to engage with and grip the object -to be pulled.

Located in the recess 4- there is the annular grapple control 15 which is provided with an upstanding key Iii. This key is seated in a longitudinalkeyway [Tim the inner side of 'thebowl and which may, or may not, be dove-tailed in cross section. As shown in Figure 2, it is dovetailed.

The key 16 projects inwardly'radially into the notch 9 of the grapple and holds the grapple against turning'relative to the bowl, but, as will be noted, the-grapple has a, limited longitudinal movement relative to the bowl.

In use the tool may be lowered into the-wall and guided to any selected distance over the object to be pulled. After the grapple has passed over said object it will grip the same and being expansible will take holdof and grip objects of different outside diameters.

Upon upward movement of the tool the seatfi' will move upwardly, relative to the spiralled face Y l2; thus contracting; the grapple into secure engagement with the object gripped thereby, and

unlessjtoo tightly stuck the'object will be re-- leased and removed from the well.

Should it be desired to release the tool from said object it may be lowered and when the bowl reaches the limit of its downward movement rela-' tive to the grapple, which remains engaged with said object, the spiralled edge 13 enters the spiralled groove 6 with the result that the grapple is expanded and thereupon, upon rotation-of-thebow-l in an appropriate direction, the;grapple;will

remain in its upper position relative to the bowl and will remain expanded even though the tool may move upwardly as the turning movement takes place. The tool should be rotated in a direction opposite the direction of the pitch and the friction between the bowl and the grapple will maintain the spiralled edge l3 in the spiralled groove 6 and thus maintain the grapple expanded. While the threads, or wickers, 14 are not, in all cases, indispensable, they are usually provided and if pitched in the same direction as the pitch of the seat 5 they will assist in releasing the grapple. A continuation of this, rotation results in rotating the grapple to thread the same off of the stuck object, thus releasing the tool from the stuck object so that the tool may be withdrawn.

The grapple control 15 including its key l6 are not indispensable but are preferably used as the grapple will thereby be prevented from becoming stuck in the bowl in its uppermost or lowermost positions.

The guide 4 may have an inside annular seal l8 seated therein to form a fluid tight seal between the overshot and the stuck pipe so that fluid may be forced down through the operating string and the tool and on down through the stuck pipe and back up around the stuck pipe to assist in releasing it.

The drawings and description are illustrative merely while the broad principle of the invention will be defined by the appended claims.

What I claim is:

1. An overshot adapted to telescope over an object to be removed from a well and comprising, a tubular bowl having an inside, spiraled, downwardly converging seat, a tubular expansible grapple in the bowl having an external face shaped to conform to the contour of, and to seat on said seat said grapple terminating at one end in a tension ring and also having a lower end notch, a tubular guide secured on the lower end of the bowl, the lower end of the bowl being internally countersunk forming an annular recess, an annular grapple control seated in said recess and provided with a projection which extends into said notch, said guide being inwardly thickened and engaging and clamping said grapple control in said recess.

2. An overshot adapted to telescope over an object to be removed from a well and comprising, a tubular bowl having an inside, spiraled, downwardly converging seat terminating in a downwardly facing shoulder, a tubular expansible grapple movably disposed in the bowl for longitudinal movement relative to the bowl, said grapple having an external face shaped to conform to the contour of, and to seat on said seat said grapple terminating at one end in a tension ring and terminating in an upwardly facing shoulder adapted to frictionally engage said downwardly facing shoulder to hold the grapple against rotation in one direction relative to the bowl, upon relative longitudinal movement of the grapple in the bowl in a direction to engage said shoulders, said grapple also having a lower end notch, a tubular guide secured on the lower end of the bowl, the lower end of the bowl being internally countersunk forming an annular recess, an annular grapple control seated in said recess and provided with a projection which extends into said notch, said guide being inwardly thickened and engaging and clamping said grapple control in said recess.

3. An overshot adapted to telescope over an object to be removed from a well and comprising a. tubular bowl and a tubular grapple in the bowl, said bowl and grapple being longitudinally movable relative to each other, said bowl having an inside spiraled downwardly converging seat terminating in a downwardly facing shoulder, said grapple having an external face shaped to conform to the contour of, and seat on said seat upon relative movement of the bowl and grapple in one direction, said external face terminating in an upwardly facing shoulder adapted to engage said downwardly facing shoulder upon relative movement of the bowl and grapple in the other direction, said grapple also having a lower end notch, a tubular guide secured on the lower end of the bowl, the lower end of the bowl being internally countersunk forming an annular recess, an annular grapplecontrol seated in said recess and provided with a projection which extends into said notch, said guide being inwardly thickened and engaging and clamping said grapple control in said recess.

4. An overshot adapted to telescope over an object to be removed from a well and comprising a tubular bowl, an internally threaded expansible tubular grapple in the bowl, said bowl and grapple being longitudinally movable relative to each other, said bowl having an inside, spiraled, downwardly converging seat whose pitch is in the same direction as the pitch of the internal threads of the grapple, said seat terminating in a downwardly facing shoulder, said grapple having an external face shaped to conform to the contour of and seat on said seat upon longitudinal movement of the bowl and grapple relative to each other in one direction to engage said threads with a stuck object, said face terminating in an upwardly facing shoulder cooperable with said downwardly facing shoulder upon longitudinal movement of the bowl and grapple relative to each other in the other direction to rotate the grapple upon rotation of the bowl in a direction to release said threads from the stuck object.

5. An overshot adapted to telescope over an object to be removed from a well and comprising a tubular bowl, an internally threaded, expansible, tubular grapple in the bowl, said bowl and grapple being longitudinally movable relative to each other, said bowl having an inside, spiraled,

downwardly converging seat whose pitch is in the same direction as the pitch of the internal threads of the grapple, said seat terminating in a downwardly facing shoulder, said grapple having an external face shaped to conform to the contour of and cooperate with said seat upon longitudinal movement of the bowl and grapple relative to each other in one direction to engage said threads with the stuck object, said face terminating in an upwardly facing shoulder cooperable with said downwardly facing shoulder upon longitudinal movement of the bowl and grapple relative to each other in the other direction to telescope the grapple over the stuck object and to rotate the grapple with the bowl upon rotation of the bowl in a direction to release said threads from the stuck object.

6. An overshot adapted to telescope over an object to be removed from a well and comprising a tubular bowl, an internally threaded, expansible, tubular grapple in the bowl, said bowl and grapple being longitudinally movable relative to each other, said bowl having an inside, spiraled downwardly converging seat whose pitch is in the same direction as the pitch of the internal threads of the grapple, said sea-t terminating in a downwardly facing shoulder, said grapple having an external face shaped to conform to the contour of and cooperate with said seat upon longitudinal movement of the bowl and grapple relative to each other in one direction to en age said threads with the stuck object, said face terminating in an upwardly facing shoulder cooperable with said downwardly facing shoulder upon longitudinal movement of the bowl and grapple relative to each other in the other direction to telescope the grapple over the stuck object and to rotate the grapple with the bowl upon rotation of the bowl in a direction to release said threads from the stuck object, said grapple also having a lower end notch, a tubular guide secured on the lower end of the bowl, the lower end of the bowl being internally countersunk forming an annular recess, an annular grapple control seated in said recess and provided with a projection which extends into said notch, said guide being inwardly thickened and engaging and clamping said grapple control in said recess.

7. An overshot adapted to telescope over an object to be removed from a well and comprising, a tubular bowl having an inside, spiraled, downwardly converging seat, a tubular expansible grapple in the bowl having an external face shaped to conform to the contour of, and to seat on said seat, said grapple terminating at one end in a tension ring and also having a lower end notch, a tubular guide secured on the lower end of the bowl, the lower end of the bowl being internally countersunk forming an annular recess, and annular grapple control seated in said recess and provided with a projection which extends into said notch.

8. An overshot adapted to telescope over an object to be removed from a Well and comprising, a tubular bowl having an inside, spiraled, downwardly converging seat, a tubular expansible grapple in the bowl having an external face shaped to conform to the contour of and to seat on said seat, said grapple terminating at one end in a tension ring and also having a lower end notch, a tubular guide secured on the lower end of the bowl, the lower end of the bowl being internally countersunk forming an annular recess and said bowl having an internal groove opening into said recess, an .annular grapple control seated in said recess andiprovided with a projection which extends intofsaid notch and said groove in interengagement with said grapple and said bowl to hold said grapple against rotation in said bowl.

9. An overshot adapted to telescope over an object to be removed from a well and comprising, a tubular bowl having an inside, spiraled, downwardly converging seat, a tubular expansible grapple in the bowl having an external face shaped to conform to the contour of and to seat on said seat, said grapple terminating at one end in a tension ring and having a plurality of longitudinally disposed slots extending from one end of the grapple and terminating in said tension ring and a longitudinally disposed slot extending from end to end of the grapple, said grapple also having a lower end notch, a tubular guide securedbn the lower end of the bowl, the lower end of ithe bowl being internally countersunk forming an annular recess and said bowl having an internal groove opening into said recess, an annular'grapple control seated in said recess and provided with a projection which extends into said notch and said groove into interengagement with said bowl and grapple to hold said bowl and grapple against relative rotation.

DEAN W. OSMUN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,678,829 Scott July 31, 1928 1,750,248 Thompson Mar. 11, 1930 2,014,804 Hinderliter Sept. 17, 1935 2,174,077 Bowen Sept. 26, 1939 2,184,681 Osmun Dec. 26, 1939 2,295,630 Bowen Sept. 15, 1942 2,491,392 Osmun Dec. 13, 1949 2,553,985 Siracusa May 22, 1951 

